The present invention relates to aqueous compositions comprising adenosine or an adenosine analogue, and at least one hydrotrope, for cosmetic use.
Adenosine is an endogenous purine nucleoside that modulates many physiological processes. It is known that in regard to stress or injury, adenosine primarily provides cytoprotection preventing tissue damage in disorders like hypoxia, ischemia and seizure (Sebastião A M, Ribeiro J A (2009), “Adenosine receptors and the central nervous system”, Handb Exp Pharmacol. 193:471-534) Adenosine is also believed to be an anti-inflammatory agent at one of its cellular signaling receptors, A2A. (Trevethick M A, Mantell S J, Stuart E F, Barnard A, Wright K N, Yeadon M (October 2008), “Treating lung inflammation with agonists of the adenosine A2A receptor: promises, problems and potential solutions”. Br. J. Pharmacol. 155 (4): 463-74)) Topical treatment of adenosine on wound sites can drastically increase tissue repair and reconstruction. (Haskó G, Linden J, Cronstein B, Pacher P (September 2008). “Adenosine receptors: therapeutic aspects for inflammatory and immune diseases”. Nat Rev Drug Discov 7 (9): 759-70; Nakav S, Chaimovitz C, Sufaro Y (2008). Bozza, Patricia. ed. “Anti-Inflammatory Preconditioning by Agonists of Adenosine A1 Receptor”. PLoS ONE 3 (5): e2107)
In the cosmetic domain, adenosine and its analogues are important active compounds for skin anti-aging due to its function on increasing DNA/protein synthesis in dermal cells. It has been broadly applied in many skin care products to improve the visual appearance of skin, such as soften fine lines and reduce wrinkles of skin and relax the muscles involved in facial movement and expression.
However, the solubility of adenosine is very limited, especially in water, which suppresses its biological potential in cosmetics. Thus, there remains a need for methods for improving the water solubility of adenosine for cosmetic use.
Published U.S. application 20040146474, L'Oreal, discloses methods for softening lines and relaxing the skin with adenosine and adenosine analogues. U.S. Pat. Nos. 6,423,327 and 6,645,513, University of Massachusetts, disclose treatment of skin with adenosine or an adenosine analogue. Published U.S. application 20070232561, King Pharmaceuticals Inc., discloses pharmaceutical compositions for promoting wound healing. The pharmaceutical compositions contain high concentration (10 to 70% w/w) of glycols and a thickening agent, and achieved a final concentration of 0.00001 to 0.10% w/w for adenosine analogues.
Published U.S. application 20080219927, A. B. Thakur et al., discloses adenosine derivative formulations for medical imaging. The formulations contain a solvent made up of water and hydroxypropyl-β-cyclodextrin to form a stable composition of adenosine analogues or derivatives that can be used for myocardial perfusion imaging. Published U.S. application 20110152214, Trustees of Tufts College, discloses a silk polymer-based adenosine release system with therapeutic potential for treatment of epilepsy.